The municipalities of Rotterdam and Amsterdam have switched on their Citrix servers again, RTL Z reports Monday. Citrix rolled out an update on Sunday-evening for the most-used versions of the system that must close a major vulnerability.
In a response to NU.nl, a spokesperson for the municipality of Rotterdam confirmed that the Citrix servers went online "early this morning". The reason for this was the new update, which is now installed on the municipality's systems. "We follow the instructions of the supplier and the National Cyber Security Center (NCSC, ed.)."
The company hopes to have closed the vulnerability in all versions on Friday. NCSC's advice to take mitigation measures and, where necessary, to disable Citrix servers is still valid.
According to NCSC, the update only helps if the system has not already been compromised. Companies that only took steps after January 9 to protect their systems could assume that there was a break-in.
Citrix vulnerability also affected ministries
The vulnerability allows malicious parties to remotely have programming code played on a network. They can then take over the entire system.
Citrix is a widely used system that is laid around existing systems like a shell and is used, among other things, to enable people to work at home. In recent weeks, the problems have affected the Ministry of Economic Affairs, hospitals and universities.